The cat does not need a passport. However, perhaps she was referring to the EU pet passport, which is a standardized document that looks like a passport book. The pet passport documents the pet's vaccinations and medications and other information
A month ago I brought a cat from the US to Cyprus. I got a EU pet passport for the cat prior to bringing the cat from the US to Cyprus. This made the process very easy. I'll explain what I did in a minute, but first your friend should contact the Israeli consulate to determine what the requirements for bringing a pet to Israel are. I expect that they may be similar to EU requirements. Note that some countries (like the UK) require quarantine or blood testing well in advance of travel.
First off, find a USDA certified Vet in the US and work with them. Not all vets are USDA-certified. They will be very helpful. The vet must be a USDA-certified vet in order for the health certificate from the US to be valid. Prior to travel, the Vet will complete the health certificate and then you will have to go to the USDA office to have the USDA Vet Officer certify the health certificate. Basically, the USDA Vet Officer is certifyiing that the vet you saw was USDA-certified and that you have all the necessary innoculations, etc. The cat will mostly have to have flea and tick treatment applied by the USDA-certified vet and also intestinal parasites pill. Of course the rabies vaccination has to be current. Bring all the documentation you have on the vaccinations and treatments with you to the USDA office. Note that depending on where you live, the USDA Vet Officer may only be in the USDA office a few days a month. Some USDA Vets cover several states. The fee for certification was $36. It may be possible to express mail all the documents if you cannot go to the USDA office.
The thing I did was to have my Vet document everything in the EU pet passport in addition to the health certificate. It was no problem for me because I am familiar with the EU pet passport, although the vet was not. I just showed him where everything needed to be documented. I do not believe that these pet passports are available in the US. It would be nice if they did.
Another thing that may be required is the cat be microchipped. In the EU the microchip must be ISO compliant (so that the EU readers can read them). The microchip must be inserted before the rabies vaccine.
The USDA health certificate will be valid for 4 months, but it is better to get it completed as close to travel as possible.
You may also have to notify the Israeli vet services prior to arrival in Israel. They may want their gov vet services to examine the pet. This may cost you some money as they do not typically keep gov vets on staff at the airport.
This being said, I went through all the hoops and paid all the fees and made all the notifications and when I arrived in Cyprus with my cat I showed the customs officer the EU pet passport. He checked the rabies vaccine info in the pet passport and waived me through. No one, I mean no one, even looked at the health certificate. But I had everything in order just in case.
Another thing is that you have to do is request from the airline to bring the pet with you. Of course there willbe a fee. If the cat and it's carrier weigh less than 8 kilos, it can go in the cabin. Otherwise it will have to go in the hold. I would never put my cats in the hold for such a long trip. Trish Nish traveled in her Sherpa carrier with me in the cabin. She was a good little cat.
Your friend should also find out what the requirements are for bringing the cat back to the US. I have never traveled to the US with a cat. I suspect that at the very least the cat will have to be examined by a vet in Israel prior to travel to the US. Your friend could get a pet passport from the Israeli vet for future travel.
When you go through security with the cat, the cat will have to be taken out of its carrier and the carrier has to be sent through the x-ray machine. You will walk through the metal detector with the cat. I have a harness and leash for my cat for this event. I put the harness on the cat before I leave home. Then at the airport, just before security, I put the leash on the cat. It's a precaution in case the cat decides to bolt (from fear) - so far so good and I haven't needed the leash, but it's better to be safe than sorry. I'd hate to be that person who cause a security incident because my cat escaped.
I hope this helps you. You can PM me if you have any other questions.